This invention relates to an automatic animal feeder for commercial or recreational use. More particularly, it relates to an animal feeder which distributes feed by vibrating the base plate and walls of a hopper so that feed is vibrated out of the opening between the bottom of the walls of the hopper and the base plate.
Automatic animal feeders are known in the art, and a variety of devices have been developed which are powered by electrical or mechanical means. Many of these prior art feeders relate to fish feeders. However, these presently known devices have a number of disadvantages and limitations which decrease their utility.
The first problem is the lack of control over the delivery of feed caused by the variety in the form of the feed itself. While some feed is available in pellet form, with individual pellets ranging up to an inch long, feed of this size is inedible or undesirable for many forms of aquatic life. Some aquatic life, because of their size or dietary needs, require that individual pieces of feed be very small. In fact, many types of immature aquatic life require that the feed be of almost flour-like consistency and some types are best raised on a flour-like feed which has been impregnated with oil. Conventional feeders normally rely on a mechanical motion to take a measured amount of feed and throw it or drop it into the water. While feeders of this type will normally work for pellet-sized feed, they have significant disadvantages and limitations when used with feed of flour-like consistency or oil-impregnated flour-like feed. For instance, wind will often carry the flour-size feed away before it hits the water. Also, flour-sized feed is susceptible to clumping together due to moisture, which interferes with the working mechanism of feeders of this type. Particularly prone to clumping is feed which has been impregnated with oil. Because of this clumping, these feeders may stop delivering feed even though feed remains in the container portion of the apparatus. Also, the quantity of feed and the rate at which it is released by automatic feeders of this design is unpredictable because of moisture, settling, or changes in flow rate as the level of feed in the storage hopper is lowered. Another problem with traditional feeders is that they are often incapable of delivering small amounts of feed for a short interval of time as required by certain species of water life. Finally, many of the mechanical feeders are unreliable because they have a large number of working parts.
Examples of these unsatisfactory features are shown in the prior art. Lehman (U.S. Pat. No. 3,195,508) discloses a mechanical "thrower", which works satisfactorily only with larger, grain-size feed. Loudon (U.S. Pat. No. 3,029,790) discloses a feeder in which the feed is dispensed through multiple apertures in the bottom of the feed storage hopper which are opened and closed by a crank. This device is incapable of breaking up fine consistency or oil-impregnated feed which has clumped together because of moisture and is susceptible to binding and clogging by finely ground feed. Fillion (U.S. Pat. No. 4,027,627) is another of the throwing feeders, with the accompanying drawbacks, mentioned above.
Bush (U.S. Pat. No. 3,741,163) and Kahrs (U.S. Pat. No. 3,730,142) are demand responsive fish feeders in which the fish bump into a pendulum which hangs from the feed hopper down into the water, and as the pendulum rocks, it dislodges feed from the hopper. Such feeders are undesirable for several reasons. First, they are demand responsive, so that no control is available over the feed rate. Also, when the pendulum tilts, the feed is essentially dumped off of a platform on top of the pendulum. Such a design could only work with large grain-size feed as finer feed would continuously flow from the feeder. Braden (U.S. Pat. No. 3,677,230) is another demand feeding apparatus similar to the Bush patent and has similar drawbacks. Additionally, the pendulum is attached to a stopper which releases feed as it is tilted from side to side by the movement of the pendulum. While this design may allow for greater control over smaller size granules of feed than the designs disclosed in Bush and Kahrs, it still suffers the other problems listed with regard to Bush and Kahrs. Another similar device is that disclosed in Rack (U.S. Pat. No. 3,688,743), which is directed to a demand feed dispenser operated by a pendulum in the water. The pendulum rotates a pin, the head of which acts as a stopper in the bottom of the hopper. Greater control may be maintained by the apparatus disclosed in the Rack patent over the delivery of finely ground feed, but there is no provision for preventing moisture from causing the feed to clump together.
Szekely (U.S. Pat. No. 3,605,697) discloses a shaker attached to the vibrating portion of an alarm clock. This design is also susceptible to the clumping of finely ground feeds and the concomitant inability to consistently dispense a precisely measured quantity of feed. Also, it is unable to dispense oil-impregnated feeds.
Therefore, it is an object of this invention to provide a device for feeding fish and other aquatic life which is capable of reliably dispensing all size ranges of fish feed.
Another object of the present invention is to provide an apparatus capable of controlling the flow rate of the feed delivered during the feeding period.
Another object of the invention is to provide a means for breaking up feed which is clumped together within the device due to moisture or the oil with which the feed is impregnated.
A further object of the invention is to provide a device with a means to deliver precisely measured quantities of feed at selected feeding intervals.
A still further object of the invention is to provide a device which can deliver all the feed stored in the hopper so that the feeder does not stop dispensing feed even though some feed remains inside the hopper.
Other objects of the invention will become apparent as the invention is described.